This invention relates to machines for polishing the surface or surfaces of workpieces, such as for example workpieces made of glass, ceramic, silicon crystals and metals. Even more particularly this invention relates to an improved such polishing machine which eliminates the need for employing a plurality of different drive motors to effect various operations of the polisher.
There are currently available in the marketplace a number of machines for polishing products such as those made from glass, ceramic, silicon crystals and metals. U.S. Pat. No. 4,916,868, for example discloses a honing, lapping or polishing machine which utilizes three disc-shaped work holders each having therein a series of circular apertures for holding workpieces, and with the discs being mounted for rotation about their respective axes and also for revolution within a surrounding, circular gear type member. One disadvantage of this mechanism is that it requires a plurality of separate electric motors for driving various parts on the machine. U.S. Pat. No. 6,045,716 also discloses a plurality of carrier devices for holding workpieces, and which carrier devices are operated independently of each other. This is typical in most prior polishing machines in which the various work carriers are driven by a plurality of independently operated DC motors.
It is an object of this invention, therefore, to provide for a polishing machine improved drive means which utilizes a single electric motor for simultaneously rotating a polishing table, and a plurality of removable workpiece holders mounted on a polishing surface of the table for rotation therewith and for rotation relative thereto.
Another object of this invention is to provide improved drive means of the type described which rotates workpiece holders and the polishing table in the same direction about their axes.
A still further object of this invention is to provide for a machine of the type described improved, circular workpiece holders retained for rotation about stationary vertical axes during rotation of the table upon which they are mounted.
Other objects of the invention will be apparent from the specification and from the recital of the appended claims particularly when read in conjunction with the accompanying drawings.
A disc-shaped polishing table, which is mounted on a machine frame for rotation by an AC electric motor coaxially about a vertical axis, has thereon an upper, generally planar polishing surface for supporting for rotation thereon a plurality of circular workpiece carriers. A plurality of rigid arms are supported on the frame above the table to extend radially inwardly thereof in angularly spaced relation to each other, and in vertically spaced relation to the polishing surface. A pair of rollers are supported on each of the arms for rotation therebeneath about spaced, vertical axes, and for rolling engagement with the outer peripheral surface of one of said carriers at angularly spaced points thereabout. One roller of each pair thereof is operatively connected to the table to be rotated thereby, and is in rolling, driving engagement with one of said carriers to effect rotation thereof while the other roller of the pair is rotated by the carrier with which it is engaged. Also, each of the carriers is annular in configuration and has a disc-shaped workpiece holder removably mounted coaxially therein to be seated on the polishing surface, and each holder has therethrough spaced openings for accommodating the ends of the workpieces that are to be polished.